The invention relates to a brush device, in particular for an electric machine, comprising at least one brush holder which has at least two brush boxes for receiving respectively one brush, wherein the brushes are mounted in the respective brush box in a displaceable manner and wherein respectively one helical spring can be braced/is pretensioned in the respective brush box between one of the brushes and a stop, and comprising at least two elastically deformable electrical conductors which are connected in each case with an end thereof to one of the brushes.
In addition, the invention relates to an electric machine comprising a brush device.
Brush devices as well as electric machines of the type mentioned above are known from the prior art. Slip ring devices or commutator devices are often provided in electric machines which serve to reverse the current fed through the coils of the electric machine. These commutator devices comprise as a rule at least two brushes which are pressed by one or a plurality of brush holders against commutator segments arranged on a rotatable shaft. In order to ensure a reliable contact between brushes and commutator segments, the brushes are often impinged with a spring force and thereby pressed against the commutator segments. Brush devices are thus, for example, known, in which helical springs are provided in the brush holder, which can be braced between the brushes and a stop formed by the end of the respective brush box.
U.S. patent application US 20070080602 thus discloses a brush device, in which two brushes are mounted in a displaceable manner in respectively one brush box in a brush holder, wherein respectively one helical spring is provided between the respective brushes and the end of the corresponding brush box. In so doing, an elastically deformable electrical conductor is provided for each of the brushes in order to electrically contact said brushes. Each electrical conductor is thereby laterally attached to one of the brushes and is routed into a space between the brush boxes and from there to a connection, which, for example, is formed by a strip conductor. The electrical conductor is thus connected laterally to the respective brush because it is not possible to route said conductor on the back side of the respective brush facing the helical spring. The lateral connection of the conductor of the respective brush is however relatively expensive to manufacture.